Sspatel

Engineer 👷 ex-ATC 🛫 interests STEM and History

[Saganism @Saganismm]

“The secret of genius is to carry the spirit of the child into old age, which means never losing your enthusiasm.”

— Aldous Huxley

[Sanjeev Sanyal @sanjeevsanyal]

Apparently, a uniform set of laws for all citizens is good for Britain but somehow not for India. A very interesting view from @TheEconomist

[Sanjeev Sanyal @sanjeevsanyal]

Teddy Roosevelt's "Man in the Arena" speech ...... reflecting the mind of an newly emerging world power

[Leo @4eo]

Interesting book. Salt by Kurlansky.

Romans used to give salarium (salt
money) to troops to buy salt and other essentials. Over time it became the word for any payment given for any work a.k.a Salary.

Did you get salt money last month?

[The Math Flow @TheMathFlow]

"Mathematical knowledge adds a manly vigour to the mind, frees it from prejudice, credulity, and superstition"
- John Arbuthnot

[Amit Schandillia @Schandillia]

When the world was building history, you obsessed with conquest. When the world was doing culture, you focused on jihad.

Now every time there’s a roll call of glory, you steal Troy from the Greeks, Gandhara from the Buddhists, Alexandria from the Romans, and everything of value from everyone.

Because you have nothing of yours to showcase. This civilizational FOMO is something you have to live with, Bilal, because that’s what you get for spending 1,400 years being a nuisance to everyone around you.

[Sspatel @Setu2352000]

@drpkmath @YouTube Excellent!

[Ash Jogalekar @curiouswavefn]

Astonishing example of fine-tuning pointed out by Nick Lane in "Oxygen": “The oxygen released by the photosynthesizers is almost completely (99.99 per cent) used up by the animals, fungi and bacteria which feed on the remains of the producers, or on each other. The apparently trivial 0.01 per cent discrepancy, however, is in fact responsible for all life as we know it. It represents the organic matter that is not burnt, but is instead buried under sediments.

Over several billion years, this adds up to a vast amount of buried organic matter. If organic remains are buried rather than eaten, then the complete re-uptake of oxygen by consumers is prevented. The left-over oxygen accumulates in the atmosphere.

Almost all our precious oxygen is derived from a 3-billion-year mismatch between the amount of oxygen generated by the primary producers and the amount used up by consumers.”

[Ash Jogalekar @curiouswavefn]

The more I ponder the phenomenon of photosynthesis the more I find myself speechless with astonishment. We take it for granted, but so many features of it - its accidental evolution, its relatively *low* efficiency, the architectural and functional marvel that is rubisco, the fact that oxygen is actually a poison and that its increase was an unmitigated catastrophe for so much of life on earth - are just unreal.

[Math Files @Math_files]

In November 2001, Chinese President Jiang Zemin visited Beijing University of Technology.

During a visit to a calculus class about derivatives, he went to the board and wrote a line from Zhuangzi:
“A one-foot rod, if you take half of it each day, will never be used up.”

He then wrote a mathematical formula to explain it and said this idea is an early form of limits.

This example from Zhuangzi’s "Tianxia" chapter shows the idea of dividing something again and again so that it keeps getting smaller and approaches zero. It shows that the basic idea behind limits existed long before modern calculus.

[Math Files @Math_files]

A biologist, a computer scientist and a mathematician are on a train, heading from England to a conference in Edinburgh.

Once over the border, they see a black sheep in a field.

“Aha!” thinks the biologist, “Scottish sheep are black!”

“Aha!” thinks the computer scientist, “There are sheep in Scotland, at least one of which is black!”

“Aha!” thinks the mathematician, “There exists a country called Scotland which contains at least one sheep, at least one side of which is black!”

[Ananth Rupanagudi @AnanthOnTrack]

An Indian scientist at Harvard discovered ATP (Adenosine Triphosphate). Then he helped create the first chemotherapy drug and the first tetracycline antibiotic. Harvard still refused him tenure. A bowling alley would not let him bowl. He died at 53, without an obituary.

His medicines save tens of millions of lives every year. Most American doctors who prescribe them have no idea what his name was. His name was Yellapragada Subbarow (Subba Rao).

He was born in 1895 in Bhimavaram, India. His father was a Sanskrit scholar who died from tropical sprue. Tropical sprue is an acquired malabsorptive disorder found in tropical regions, characterized by chronic diarrhea, weight loss, and severe nutritional deficiencies. It is most commonly associated with deficiencies in vitamin B12 and folic acid, resulting in anemia, fatigue, and glossitis. The same disease killed two of his brothers. As a child, Subbarow watched them fade away and decided he would spend his life fighting disease.

He failed his school exams twice. Passed on the third attempt. His future father-in-law paid for his medical school books. Subbarow married his daughter and repaid the debt. In October 1922, he arrived in Boston with borrowed money and broken English. He was 27. He entered Harvard Medical School and joined the biochemistry PhD program.

He began working under a senior researcher named Cyrus Fiske. Long hours. Little pay. But he was at Harvard, and he did not care. In 1925, they developed the Fiske-SubbaRow assay, a method for measuring phosphorus in body fluids. It is still used today in kidney failure testing, vitamin D testing, and prostate cancer work. It became one of the most cited methods in biochemistry history.

Then they found something even bigger in 1926 - ATP - Adenosine triphosphate. The energy molecule that powers every cell in every living thing on Earth. That discovery changed biochemistry. It also proved that the 1922 Nobel laureate had been wrong about how muscles worked. Muscles did not run on glycogen. They ran on ATP.

Subbarow earned his PhD in 1930. He stayed at Harvard for another decade. Paper after paper. Discovery after discovery. And every year, Harvard refused to promote him. The biochemistry department had never given tenure to a foreigner. They were not going to begin with an Indian.

His colleagues took him fishing. Played tennis with him. Came to dinner at his home. Then voted against him year after year. Outside the laboratory, he met the same wall. He bought an airplane and learned to fly because he loved flying. Once, he tried to go bowling. The local alley refused him entry. The sign said it was “open only to the Caucasian race.”

Then Fiske turned against him. The senior researcher began blocking Subbarow’s discoveries out of jealousy. Some of Subbarow’s work had to be rediscovered years later by other scientists because Fiske kept his findings hidden.

May 1940. Harvard denied him tenure for the last time. After 17 years of groundbreaking work, he walked away. Lederle Laboratories in New York hired him as Associate Director of Research. By the end of the year, he was Director. In the next eight years, he changed medicine. He developed diethylcarbamazine, an oral medicine that killed the tropical worms crippling American soldiers in the Pacific. The World Health Organization still uses it.

He isolated folic acid from liver and worked out how to produce it on a large scale. Today, folic acid in pregnancy prevents birth defects in tens of millions of pregnancies every year. The same family of diseases that killed his father and brothers became preventable because of him.

Then Dr. Sidney Farber called from Boston with an idea: maybe a drug that blocked folic acid in cancer cells could kill childhood leukemia. Subbarow’s team created the drug. They called it Aminopterin. In December 1947, Farber gave it to an eight-year-old boy dying from leukemia. Within weeks, the cancer cells began to disappear.

It was the first chemotherapy drug in history. The first time anyone had put cancer into remission using a pill. Subbarow’s team later refined it into Amethopterin, now known as methotrexate. It became a gold standard treatment for leukemia, lymphoma, breast cancer, and lung cancer. Then rheumatoid arthritis, psoriasis, and Crohn’s disease. The World Health Organization lists it as an essential medicine. Tens of millions of people use it every year.

In 1948, his lab produced Aureomycin. The first tetracycline antibiotic - a broad-spectrum one that killed typhus, cholera, pneumonia, and many bacteria that penicillin could not touch. It opened the door to the whole tetracycline family: doxycycline, minocycline, and drugs still used today against plague, malaria, anthrax, and drug-resistant infections.

He was 53 years old. He had created medicines that would save tens of millions of lives. August 8, 1948. Yellapragada Subbarow suffered a heart attack at his home in New York and died. No American newspaper gave him a front-page obituary. No university held a memorial. The Nobel Committee never honoured him. His own colleague George Hitchings later won a 1988 Nobel Prize for work built directly on Subbarow’s foundation. Subbarow was not even nominated.

In 1950, Argosy magazine published a feature about him titled “Miracle Man of the Miracle Drugs.” It began with a line that still hits hard. “You’ve probably never heard of Dr. Yellapragada Subbarow. Yet because he lived, you may be alive and are well today. Because he lived, you may live longer.”

Most Americans had not heard of him in 1950. Most still have not. Harvard has never officially honoured him. American medical schools mostly do not teach his name. The Nobel Committee that honoured Hitchings for work built on his foundation never corrected the record. Every methotrexate prescription written today remains silent about the man behind it.

India remembers. The government issued a postage stamp for his 100th birthday. His childhood home became a museum. Indian medical schools teach his name. But the country that denied him tenure, refused to let him bowl, and allowed him to die unknown - the same country that uses his drugs every day - still mostly does not know him.

Here is the truth. If someone you know has ever taken methotrexate for cancer or an autoimmune disease. If someone you love has taken folic acid during pregnancy. If you have ever been prescribed doxycycline for an infection. That was him. Yellapragada Subbarow. Born 1895. Died 1948. Saved tens of millions of lives, while a country he loved barely knows what it owes him.

Please remember his name and let your near and dear know about this little-known scientific legend born on this soil but never got the true recognition that he deserved. A story you need to know. A story all of us need to know. #Medicine #Unknownlegends @centerofright @KiranKS

[keerthik śaśidharan @KS1729]

epsilontics — a word for the epsilon-delta based analysis that students of calculus must first wrap their heads around…
[I had never heard of it till today!]

[Mathematica @mathemetica]

On this day in 1811, Amedeo Avogadro published his famous hypothesis: equal volumes of gases at the same temperature and pressure contain equal numbers of molecules.

This became Avogadro’s Law and gave us the mole concept with Avogadro’s number (6.022 × 10²³).

[Mathematica @mathemetica]

“What exactly is mathematics? Many have tried but nobody has really succeeded in defining mathematics; it is always something else. Roughly speaking, people know that it deals with numbers, figures, with relations, operations, and that its formal procedures involving axioms, proofs, lemmas, theorems have not changed since the time of Archimedes.”

— Stan Ulam

[Gerardo L. Munck @GerardoMunck]

Hobsbawm on the Modern World

One of the treats for those who are interested in history is to read Eric Hobsbawm's four volumes on different ages, from the French Revolution to the end of the Cold War. They make for a very rewarding reading.

Thread with links to all four books.

[Math Files @Math_files]

Pierre Simon de Laplace reading his Celestial Mechanics (19th-century lithograph).

[Mathematica @mathemetica]

Many who have had an opportunity of knowing any more about mathematics confuse it with arithmetic, and consider it an arid science. In reality, however, it is a science which requires a great amount of imagination.

— Sofia Kovalevskaya